[mrtg] Collecting non-rate data and RRD

[Alex van den Bogaerdt]

On Tue, Dec 18, 2007 at 09:50:22AM -0500, Tuc at T-B-O-H.NET wrote:

> 	Is there some way or some option that would be able to 
> selectively fix the timestamps that it uses to put the data into the 
> RRD file for the ones where I need to do that? Since I really only use
> MRTG to put the value into the RRD, and really nothing else, should I
> just write my own program to load the RRDs?

Sounds reasonable.  But then?  You're not only dealing with normalization,
you're also dealing with consolidation.  What if you have (say) 1200 rates
to display, on a (say) 400 pixels wide graph?

One suggestion would be to store MIN, MAX and AVERAGE. I do this for
temperatures (just one data input).

Then compute the difference between min and max, display an area and
finally draw a line showing the average.

DEF:min=your.rrd:x1:MIN
DEF:max=your.rrd:x1:MAX
DEF:avg=your.rrd:x1:AVERAGE
CDEF:dif=max,min,-
AREA:min
STACK:dif#00F:range
LINE1:avg#000:average

You could have a step size of 1, and an RRA which uses 300 steps per
row (resulting in 5-minute per row) instead of the current 300 seconds
per step and one step per row (also 5-minute rows).

If you're not interested in averages, leave'm out.

This is just a suggestion which may or may not apply to your situation.

HTH
-- 
Alex van den Bogaerdt
http://www.vandenbogaerdt.nl/rrdtool/